SunCatcher sound studies continue; County audio expert’s testimony doesn’t jive with Tessera’s

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by Vince and Mary Palermo

A very animated Matt Jones gave a detailed presentation on the sound issues surrounding the Tessera Suncatchers.

On Monday, December 6, the Saguache County courtroom was packed for the Tessera Solar public hearing.

The hearing  began with  Tessera  giving their presentations. Then Russell Engineering, the firm hired to research all the project details for the Commissioners, spoke.

The third presenter was Matt Jones, an acoustic engineer, from Mestre Graves.  He was hired to be an unbiased reviewer of the noise report that was prepared for Tessera by HDR (an architectural, engineering, and consulting firm).  There had been considerable opposition to the validity and accuracy of the HDR noise report, which led to engaging the company, Mestre-Greves, which has a high professional reputation.  Matt was able to dig through the raw data collected by HDR, find some errors of computer analysis, and come up with an analysis very different from the Tessera report.  In short, Matt reported the noise level at the project boundary, produced  by 5,728 SunCatchers, would be 70dBA, and a half mile away it would be 55dBA.  70dBA is very loud noise and is equivalent to a busy, four-lane highway.

These numbers are critical because the CO State statute on noise states that 55dBA is the legal limit.  The statute further imposes a 5dBA penalty for “shrill and impulsive noise” which lowers the legal limit to 50dBA.  Matt Jones and his staff considered Suncatcher noise to be shrill, therefore according to the CO statutes,  the noise limit for SunCatchers  is 50dBA. Only HDR disagreed that the noise was shrill.  Tom Dessain proved the point by bringing his amplifiers and loudspeakers and played SunCatcher noise on the front lawn of the Courthouse.

We went to Maricopa, AZ in September and measured the noise level at Tessera’s 60-SunCatcher plant.  Using these sound measurements, and accounting for sound reduction from the 500-foot setback, we calculated a noise level of close to 70dBA at the Saguache project property boundary.  Our noise levels are in agreement with Matt Jones’, and, in our opinion, prove that the HDR report for 5,728 SunCatchers is incorrect and misrepresents the “real time” noise that would be generated.

In summary, the noise level would be 20dBA over the CO statute (15dBA if “shrill” is not counted) and exceeds the CO law limit.  Additionally, the noise level is 27dBA over the County Solar Guidelines using HDR’s ambient, and 45decibels over the Guidelines using our ambient sound level measurements.

Elsewhere, Interior Secretary Ken Salazar has approved a 28,000 SunCatcher plant in  Imperial Valley, CA, and a 26,500 SunCatcher project in San Bernadino, CA—both on BLM land.  The parent company of Tessera is NTR, an Irish conglomerate investing in green energy projects and waste management.  However, NTR lost $280 million dollars in the last fiscal year.  The future picture of SunCatcher is uncertain since both CA projects are experiencing opposition, and a Texas SunCatcher project recently had funding support withdrawn.

In comparing SunCatchers to other solar technologies, its cost per installed watt is more than two times that of PV.  Further, it has the highest maintenance cost.  SunCatchers may not play out to be cost-competitive.

A second final public meeting will be scheduled. Written comments are still being accepted. It is important our Commissioners hear each and every concern. Everyone will be heard this time.

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